A Groundbreaking Discovery: Orangutan Rakus Applies Medicinal Plant to Fresh Wound, Prompting Evolutionary Questions

In the Suaq Balimbing research area of Gunung Leuser National Park in Indonesia, an orangutan male named Rakus was observed exhibiting a unique behavior. He applied a plant with medicinal properties to a wound under one of his eyes, using the sap of the climbing plant Akar Kuning (Fibraurea tinctoria) and covering it with chewed leaves. This behavior had never been seen before in a wild animal and took place in June 2022.

Researchers from the Max Planck Institute for Animal Behavior in Germany and Universitas Nasional in Indonesia observed Rakus’ behavior and noted how he selectively treated his wound with the plant’s juice. The intentionality of this behavior suggests that medical treatment of wounds may have originated from a shared common ancestor of humans and orangutans.

While other primate species have been observed using plants with medicinal properties, it was the first time that a great ape species applied them to fresh wounds. Rakus’ wound healed in five days and was completely cured within a month due to the application of the plant’s juices. This behavior raises questions about the intentionality of such actions in non-human animals and how they develop.

The potential evolutionary origins of this behavior shed light on the existence of self-medication in our closest relatives and provide insights into the broader concept of wound medication among great apes. It is possible that Rakus’ innovative behavior may have been absent in the behavioral repertoire of the Suaq orangutan population until now, highlighting the importance of continued research on animal behavior and its evolutionary implications.